MATLAB Matlab Displaying the Fit Equation On graph.

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To display the fit equation on a MATLAB graph, first use the polyfit function to obtain the coefficients of the linear fit. The coefficients can be extracted and formatted into a string representing the equation, such as "y = 0.0003x + 0.0414". The text function can then be used to place this equation on the graph at specified coordinates. This method allows for automatic generation of the equation without manual input. The provided code successfully demonstrates how to implement this functionality.
Arman777
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I have a lineer data and I want to write the equation of it on the graph.
The x-axis is inverse distance (1/m) and I showed as "d"
The y-axis is capacitance (C) and I showed it like "C"
My data name is d_C

Here my codes that I used for now
>> d=d_C(:,1);
>> C=d_C(:,2);
>> plot(d,C,'go');
>> hold on
>> xlabel('Inverse Distance (1/m)','Fontsize',21)
>> ylabel('Capacitance (C)','Fontsize',21)
>> title('Inverse Distance vs Capacitance,Part (A)','Fontsize',23)
>> grid on
>> p = polyfit(d,C,1)

p =

0.0003 0.0414

>> Cfit=polyval(p,d);
>> plot(d,Cfit,'-b');
>> h = legend('Data','Best fit','Location','southeast');
>> set(h,'Fontsize',20);

I just need to write the equation on the graph like probably y=0.0003x+0.0414 (I am not sure about this though).I need codes.I can't do it on manually

Any help would be great
Thanks
 

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From a MATLAB newsgroup post:

[p]=polyfit(...);
a = p(1)
b = p(2)
polyfit_str = ['y = ' num2str(a) ' *x + ' num2str(b)]
% polyfit_str will be : y = 4*x + 2
text(10,10,polyfit_str);
 
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Thanks a lot.I did it
 

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